fix memorydump hang

deps/oblib/src/lib/alloc/memory_dump.cpp

@@ -352,10 +352,11 @@ int label_stat(AChunk *chunk, ABlock *block, AObject *object,
     } else {
       hold = align_up2(chunk->alloc_bytes_ + ACHUNK_HEADER_SIZE, get_page_size());
     }
-    void *label = &object->label_[0];
-    void *end = memchr(label, '\0', sizeof(object->label_));
-    int len = end ? (char*)end - (char*)label : sizeof(object->label_);
-    ObString str(len, (char*)label);
+    char label[AOBJECT_LABEL_SIZE + 1];
+    STRNCPY(label, object->label_, sizeof(label));
+    label[sizeof(label) - 1] = '\0';
+    int len = strlen(label);
+    ObString str(len, label);
     LabelItem *litem = nullptr;
     LabelInfoItem *linfoitem = lmap.get(str);
     if (NULL != linfoitem) {

deps/oblib/src/lib/alloc/memory_dump.h

@@ -102,7 +102,7 @@ struct LabelInfoItem
   void *block_;
 };
 
-typedef common::hash::ObHashMap<ObString, LabelInfoItem> LabelMap;
+typedef common::hash::ObHashMap<ObString, LabelInfoItem, hash::NoPthreadDefendMode> LabelMap;
 
 using lib::AChunk;
 using lib::ABlock;